5th Metatarsal Neck Fracture
Summary
5th metatarsal neck fractures result in pain and swelling on the outside part of the forefoot. They occur following an acute injury, often from jamming the foot against a solid object. Treatment is usually non-operative in a walker boot, with limited mobilization through the heel or non-weight bearing on crutches. Occasionally the fracture will need to be repositioned so that it heals in an appropriate position.
Clinical Presentation
An acute injury to the outside part of the front of the foot (base of the little toe) may lead to a 5th metatarsal neck fracture. Symptoms will include pain, swelling, and great difficulty walking. Typically the injury will occur from a direct blow, such as dropping an object on the foot, or from jamming the outside of the foot against a solid object, often with an associated twisting motion. Patients with low bone density (osteoporosis) may be at greater risk for this injury.
Physical Examination
Physical examination will identify swelling of the outside part of the forefoot. The area will be painful to touch. If the fracture is displaced, the bone (5th Metatarsal head) may be prominent, creating a lump against the skin either on the top, bottom, or outside of the foot. There may be some sensation of numbness or tingling in the 5th toe.
Imaging Studies
X-ray of the foot will reveal the fracture. This will allow the physician to see if the fracture is displaced, and combine with the physical exam findings will determine whether the fracture position is acceptable to allow non-surgical treatment.
Treatment
Non-Operative Treatment
Treatment of 5th metatarsal neck fractures is usually non-operative. If the fracture is not displaced or only minimally displaced, it may be treated with rest and immobilization to allow healing. Relative immobilization in a stiff sole shoe or walker boot for 6-8 weeks is usually adequate. Crutches non-weight bearing or heel walking may prevent further displacement. Full recovery of function often takes many months.
If the bone is sufficiently out of position, it will need to be manipulated into a better position. Whether there is excessive displacement of the fracture is usually determined by the surgeon, based on the clinical examination and the x-ray findings. If the bone is going to heal in a flexed position, or if allowing it to heal in its present position will cause a permanent lump on the bottom, top, or side of the foot, then manipulating it back into a better position is indicated. A manipulation involves moving the bone into an improved position and may be done under local anesthetic. Once this has been done, typical non-operative treatment of immobilization and crutches non-weight bearing, or heel walking is instituted.
Surgical Treatment
Occasionally the fracture will be markedly displaced and surgery will be required. In this instance, the fracture may be manipulated back into place and stabilized with a wire (pin). In rare instances, it may be necessary to open up the fracture and fix it with screws or a small plate in order to stabilize it in an improved position. Once this has been done, the typical recovery again involves a period of immobilization in a cast, boot, or stiff sole shoes for 6 or more weeks, allowing for appropriate healing. The total recovery time before complete unrestricted activities may be resumed is often 6 months or more.
Edited on September 17th, 2023
Originally edited by Michael Shereff, MD and Paul Juliano, MD
sp/9.17.23